Underlying revenue grew by 40% with repeat business generating more than 80% of all revenue. Research Now also added 250 clients in 2008 for a total of 1,000.
The firm's pre-tax profit topped £5.7m, up from £0.3m in 2007.
Chris Havemann, Research Now chief executive, said: "This past year has been hugely successful for .
"During 2008, we achieved financial results significantly ahead of expectations and consolidated our position as one of the leading global players in the online survey fieldwork industry.
"We had a good start to trading in the new financial year but, like most companies today, are naturally cautious about extrapolating these positive results.
"We remain focused on managing our operations to achieve profitable growth in 2009."